How Catholic were the Irish?

Not very, according to this article in this week's Irish Echo. 150 years ago Archbishop Cullen of Dublin and Archbishop Hughes of New York were so distressed by the fact that such a large portion of the Irish population was Catholic in name only that they initiated a "devotional revolution".

In pre-Famine Ireland, for example, only 30 to 40 percent of the population attended Mass and many who identified themselves as Catholic had virtually no knowledge of the faith's dogma and practices. Worse still, many still clung to pre-Christian pagan rituals and beliefs that had never fully died out after Ireland was converted to Christianity by Patrick and his successor missionaries. The response of Cullen and Hughes was to launch a campaign to instill faith, orthodoxy, and obedience among the people, a process historian Emmet Larkin famously dubbed, the "devotional revolution."

Maybe this is a well known fact of Irish history, but I wasn't aware of it.